1. Field of the Invention
The present invention relates to switch mode power supplies for converting DC input power to a regulated DC output potential. More particularly, the present invention relates to switch mode power supplies of the aforementioned type which have low noise.
2. Description of the Prior Art
Switch mode power supplies are known having two separate switch mode power supplies each containing a switch operated 180.degree. out of phase with respect to the other. See U.S. Pat. Nos. 4,386,311, 4,533,836 and 4,618,919. None of the aforementioned switch mode power supplies provides a phase lock loop in which the on and off times of the switches are phase locked together to insure the best possible matching of the duty cycle and a 180.degree. out of phase relationship of the switching of each of the switching elements.